1. Field of the Invention
The present invention relates to a steering mechanism for automotive vehicles, and more particularly to a telescopic steering mechanism of the type which includes first and second support members telescopically coupled with each other for relative movement, a first shaft rotatably carried by the first support member, a second shaft rotatably carried by the second support member and telescopically coupled with the first shaft for rotation therewith, a feed screw shaft arranged in parallel with the first and second shafts and rotatably carried by the first support member, and a feed nut fixedly mounted on the second support member and threadedly coupled over the feed screw shaft for effecting relative movement of the first and second support members in accordance with rotation of the feed screw shaft.
2. Description of the Prior Art
In Japanese Patent Early Publication No. 60-4464, there has been proposed such a telescopic steering mechanism as described above wherein the first support member is mounted on a vehicle body structure, and the second shaft is provided thereon with a steering wheel. In the telescopic steering mechanism, it is required to connect the first and second shafts to each other without causing any undesired gap therebetween in order to prevent vibration of the steering wheel and enhance a feel in steering operation. It is further required to eliminate undesired gap between the feed screw shaft and nut in order to retain the steering wheel in place. In Japnanese Patent Early Publication No. 60-188614, there has been proposed a mechanism which is arranged to satisfy the requirements. However, undesired vibration of the support members may not be eliminated due to relative movement thereof. Furthermore, if there is an error in machining of the feed screw shaft and nut, undesired movement or vibration of the support members will occur during rotation of the feed screw shaft. This causes undesired vibration of operation levers mounted on the second support member.